Custom PC, Issue 133

This month’s Hobby Tech is an absolute giant: seven pages long, owing to a bonus two-page review of the Nvidia Jetson TK1 development board – and many thanks to the guys at Zotac for granting me exclusive access to the UK’s only press sample ahead of its retail launch! The usual five pages are filled with a tutorial on using relays with the Raspberry Pi, an in-depth look at the Phenoptix MeArm, and a tour of the excellent DOSBox software.

The Jetson TK1 is a good place to start. It’s no Raspberry Pi: launching at £199.99 via Maplin – despite a far lower $192 US RRP – the board is designed for developers with big pockets. Despite this, it may actually be worth the cash: it’s by far the fastest single-board computer I’ve ever had on my test bench, with four 2.3GHz Cortex-A15 CPU cores, a fifth ‘Shadow Core’ for background tasks, and 192 Kepler-class graphics processing cores on its sadly actively-cooled chip. There are, however, issues that will trouble hobbyists looking to use the system. Most surprising of these is a lack of OpenCL support, despite the Tegra K1 on which the Jetson TK1 is based supporting it just fine.

From the high-end to the pocket-friendly with the next review: the Phenoptix MeArm. Supplied by Ben Gray, its designer, the MeArm is a kit of laser-cut acrylic parts and a selection of hobby servos for building a desktop robotic arm. Compatible with anything that can drive servos – or even things, like the Raspberry Pi, that can’t, if you add an I2C controller board – the MeArm is a fascinating entry point to hobbyist robotics, and doubly so thanks to its open nature and extremely low cost.

The tutorial this month is an extension to the Twitter-connected doorbell which appeared in Issue 130. Although the original design worked fine, it lacked an audible alert. The solution: using a relay to trigger the original doorbell’s sounder unit, turning my design into a drop-in upgrade for any wired doorbell while also teaching the basics of how relays can extend the capabilities of a microcontroller or microcomputer platform.

Finally, DOSBox. While I’m a big believer in using real-metal hardware for my vintage computing, even I have to admit that sometimes emulators can be extremely handy – and DOSBox is one of the handiest around. More properly termed a simulator, DOSBox allows you to run old MS-DOS software on modern systems – complete with filters that improve the graphics and full network support. Designed primarily for gaming, its compatibility with images created using the KryoFlux – reviewed in Issue 131 – mean it’s perfect for retrieving data from ageing floppy disks, as well as playing Doom the way it should be played!

All this, plus a bunch of other interesting things written by people who aren’t me, can be yours with a trip to your nearest newsagent or supermarket. If you’d prefer not to leave the house, try a digital copy via Zinio or similar services.

The 2019-20 European @astro_pi Challenge is now open! Students can now write a program and have it run on the International @Space_Station. It’s literally out of this world! Listen to @astro_luca and get inspired! https://t.co/dk57sx2nyL

New @CustomPCMag alert, with a detailed look at the #RaspberryPi4's thermal performance with a range of passive and active cooling options, the La Frite SBC, and a review of The Friendly Orange Glow. Enjoy! https://t.co/u1ut6kd1e9

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